The present invention relates generally to an apparatus and method thereof for withdrawing fluids, and more particularly to an apparatus and method capable of percutaneous or direct removal of blood and other body fluids.
Reconstructive and plastic surgery often involves the transfer of tissue to deep defects, where skin grafts would not be beneficial. During such transfer, the harvested tissue is without blood flow. If the blood flow is not restored quickly, due to microvascular complications, part or all of the tissue may become necrotic and the skin flap will fail. One such complication, venous congestion, involves inadequate venous drainage with a patent arterial inflow, and is due to tissue edema, venous thrombosis, leukocyte aggregation, or the fact that in some cases, microvascular reconnections of the venules are not surgically possible.
By way of background, skin flaps are a common feature utilized by plastic surgeons to reconstruct defects and to cover deep wounds in which a skin graft or replacement is not feasible because a patent vascular bed is absent. A skin flap is a multi-layered tissue that includes dermis, epidermis, subcutaneous tissue, fasciocutaneous, myocutaneous, osseocutaneous, and sometimes muscle tissue, sensory tissue, and possibly underlying adipose tissue, which is based on its own microvascular network. There are many thousands of cases each year that require the use of skin flaps to some degree during a medical procedure whereby these procedures can cost thousands of dollars. Reconnection of arteries to establish adequate arterial flow is vital for the ultimate success of these microsurgical procedures.
Nonetheless, skin flaps with proper arterial flow can still have compromised venous outflow, known as venous congestion, for a variety of reasons. Venous insufficiency has adverse effects, and leads to a majority of the failures in replantation surgeries. Venous congestion is a clinical problem in which extensive effort has been spent in attempts to alleviate or prevent its onset.
As a result, fluid transport techniques such as medicinal leeches are used as a treatment option in these cases to promote nutritive blood flow. The medicinal leech is currently used to initiate blood flow and reduce tissue swelling in skin grafts or replanted digits, and to promote nutritive blood flow. The medicinal leech attaches to its host utilizing three semicircular jaws containing approximately sixty (60) pairs of cutting teeth to create a xe2x80x9cYxe2x80x9d shaped incision 1 to 2mm in diameter. Once attached, the bioactive saliva is secreted between each pair of teeth, and the nervous system stimulates the pharynx to pump peristaltically, creating a negative pressure, which aids in driving blood flow into the leech. Leeches will feed until stretch receptors are stimulated by distention in the body. It has been reported that feeding on large mammals, if allowed to proceed undisturbed, will last from 20 to 60 minutes, in which time the leech will ingest 5 to 15 ml, which is up to ten times the initial body weight. Once detached, the bite wound will continue to bleed, which is thought to be an important portion of the therapy. The wound will xe2x80x9coozexe2x80x9d up to 50 ml more in the 24 to 48 hours after feeding. In order for this secondary part of the treatment to be effective, the wound must be continuously cleared of thromboses that form on the patient""s skin surface.
The use of leeches establishes a zero or negative pressure outlet for several vessels in the congested area. With the outlet, flow can resume at a basal level, supplying minimal necessary nutrients to the flap. If the flap can survive long enough due to this artificial flow, vessel reconnections can form, leading to survival of the flap.
As stated previously, one of the major factors in a successful tissue transplantation or replantation is the reestablishment of blood flow. The most common cause of flap failure is venous insufficiency, which can be treated with the use of medicinal leeches. However, the use of leeches carries the risk of infection and offers poor flow control. Potential problems for the patient that can arise with the use of the medicinal leech range from psychological problems, such as fear and disgust, to pharmacological problems in nature. Once a patient is comfortable with the procedure, there are other potential problems that can arise. Leeches rely on bacterium for the digestion of the ingested blood, due to the lack of proteolytic enzymes within the gut. One such bacteria is Aeromonas hydrophilia, a gram-negative rod, which has led to seprcaemia, pneumonia and gastroenteritis in humans. These bacteria may be ejected into the patient and cause infection. Infection rates of up to 20 percent have been linked to A-hydrophilia from leeches. Some patients experience anaphylaxis and allergic responses to the bioactive saliva of leeches, while others exhibited excessive scarring from the bite wound site. Continued leech use and persistent bleeding from the wound can result in a significant loss in blood volume. Hemoglobin levels can drop by 1 to 2 gm percent over a five day treatment due to the amount of blood lost, thus requiring a blood transfusion. Finally, if the leech is not monitored, it may wander to a more perfused region of the body to initiate feeding, rendering the treatment useless. Leeches are a widely used clinical tool today as evidenced by Biopharm Ltd. marketing 50,000 leeches per year, while Leeches USA Ltd. typically supplies 20,000 leeches per year. Due to these potential shortcomings of medicinal leeches, alternative methods to leech treatments would be very important to the future of microsurgery.
An alternative approach to medicinal leeches is a mechanical leech disclosed by Smoot in an article entitled xe2x80x9cMechanical Leech Therapy to Relieve Venous Congestion.xe2x80x9d It appears that the Smoot device is arranged with an elongated suction chamber with an inflow port for heparinzed saline and an outflow port for continuous suction. In operating mode, the Smoot-device is placed over a biopsy wound measuring 4 mm in diameter and suction is adjusted to achieve a negative pressure.
While the Smoot device appears to overcome some of the psychological and pharmacological failings of traditional medicinal leeching, as it attempts to replace a natural leech, it nevertheless has its own shortcomings. In this regard one shortcoming of the Smoot device is that it is not self-contained. Another major shortcoming relative to the present invention is that the suction pressure of the Smoot device is extremely large (i.e., xe2x88x9280 mmHg), and can not be varied cyclically. Cyclic variations are useful to maintain good flow and prevent blood clotting and/or clogging of channels. Such a large negative pressure, as required by the Smoot device, could collapse blood vessels and compact tissue, leading to clogging of transport channels. Another shortcoming of the Smoot device is that the outlet size of the biopsy wound is much greater than the required insertion of the present invention and could even be considered a wound that is detrmental to the patient A further shortcoming of the Smoot device is that the flow of heparinized saline leads to the susceptibility of spillage. An additional shortcoming of the Smoot device is that the device itself is not contained within a self-powered unit. The Smoot device is also unlikely to work on a clinically venous congested flap. A final shortcoming of the Smoot device is that a punch biopsy is required in the flesh of the subject prior to the xe2x80x9cleechxe2x80x9d being used, and consequently an increased risk of contamination. Clinicians have previously used skin excisional wounds(large area wounds) to treat seriously coagulated skin flaps. So the Smoot device essentially adjusts suction to a large area wound and would not be effective for venous congested flaps.
There is therefore a need in the art for an effective mechanical leech apparatus for percutaneous or direct removal of blood and other body fluids which does not suffer the disadvantages associated with a medicinal leech and/or conventional mechanical leeching methods.
A novel approach for withdrawing or infusing fluids, and more particularly to an apparatus and method capable of percutaneous or direct removal of blood and other body fluids, or infusion of medicinal, therapeutic, bioactive mixtures.
In one aspect, the present invention features a fluid transport apparatus for withdrawing fluid from a target, the fluid transport apparatus comprising: at least one fluid collection chamber having a target wall and a distal wall opposite of the target wall, whereby the target wall is adapted for being mated against the target while the transport apparatus is in use; an actuator means that at least partially forms a portion of the distal wall, the actuator means reciprocates when activated; at least one cutting device attached to the target wall of the fluid collection chamber and extending away from the fluid collection chamber, each such cutting device having at least one passage for transporting fluid there through; and a power supply operatively connected to the actuator means for activating the actuator, the actuator means reciprocates in an upward and downward motion relative to the target when activated, whereby the upward motion expands the volume of the collection chamber to provide a negative pressure in the fluid collection chamber relative to the pressure of the target whereby the negative pressure causes the fluid to be transported from the target into the fluid collection chamber.
In another embodiment the present invention features a fluid transport apparatus for withdrawing fluid from a target, the fluid transport apparatus comprising: at least one air storage chamber having an intermediate wall and a distal wall opposite of the intermediate wall; at least one fluid collection chamber having a wall that is defined by the intermediate wall, the collection chamber further including a target wall opposite of the intermediate wall, whereby the target wall is adapted for being mated against the target while the transport apparatus is in use; an actuator means that is in mechanical communication with the distal wall, the actuator means reciprocates when activated; at least one cutting device attached to the target wall of the fluid collection chamber and extending away from the fluid collection chamber, each such cutting device having a passage for transporting fluid there through; and a power supply operatively connected to the actuator means for activating the actuator means, the actuator means reciprocates causing the distal wall to reciprocate in an upward and a downward motion relative to the target when activated, whereby the upward motion expands the volume of the air storage chamber to provide a negative, pressure in the air storage chamber and fluid collection chamber relative to the pressure of the target and whereby the negative pressure causes the fluid to be transported from the target into the fluid collection chamber.
In another embodiment the present invention features a detachable fluid transport apparatus for withdrawing fluid from a target, the detachable fluid transport apparatus comprising a first section that is in communication with and detachable from a second section, the apparatus comprising: an attachment means that fastens the first and second sections so as to be in communication with one another and to be detachable from one another. Wherein the first section comprises: at least one fluid collection chamber having a target wall and a distal wall opposite of the target wall, whereby the target wall is adapted for being mated against the target while the transport apparatus is in use; and at least one cutting device attached to the target wall of the fluid collection chamber and extending away from the fluid collection chamber, each such cutting device having a passage for transporting fluid there through. Wherein the second section comprises: an actuator means that is in mechanical communication with the distal wall; and a power supply operatively connected to the actuator means for activating the actuator means, the actuator means reciprocates causing the distal wall to reciprocate in an upward and a downward motion relative to the target when activated, whereby the upward motion expands the volume of the air storage chamber to provide a negative pressure in the air storage chamber and fluid collection chamber relative to the pressure of the target and whereby the negative pressure causes the fluid to be transported from the target into the fluid collection chamber.
Another embodiment of the present invention is a fluid transport apparatus for infusing fluid into a target, the fluid transport apparatus comprising: at least one fluid dispenser chamber having a target wall and a distal wall opposite of the target wall, whereby the target wall is adapted for being mated against the target while the transport apparatus is in use; an actuator means that is in mechanical communication with the distal wall, the actuator means reciprocates when activated; at least one cutting device attached to the target wall of the fluid dispenser chamber and extending away from the fluid dispenser chamber, each such cutting device having a passage for transporting fluid there through; and a power supply operatively connected to the actuator means for activating the actuator, the actuator means reciprocates in an upward and downward motion relative to the target when activated, whereby the upward motion reduces the volume of the fluid dispenser chamber to provide a positive pressure in the fluid dispenser chamber relative to the pressure of the target whereby the positive pressure causes the fluid to be transported from the fluid dispenser chamber into the target.
Another embodiment of the present invention is a fluid transport apparatus for withdrawing target fluid from a target, and infusing storage fluid into the target the fluid transport apparatus comprising: at least one fluid collection chamber having a collection target wall and a collection distal wall opposite of the collection target wall, a collection side wall that connects the collection distal wall with the collection target wall, whereby the collection target wall is adapted for being mated against the target while the transport apparatus is in use; at least one fluid dispenser chamber having a storage target wall and a storage distal wall opposite of the storage target wall, a storage side wall that is proximate to or integral with the collection side wall so as to connect the storage distal wall with the storage target wall, thereby forming a generally common side wall defined by the side walls being adjacent or integral with one another, and whereby the storage target wall is adapted for being mated against the target while the transport apparatus is in use; an actuator means that is in mechanical communication with the common side wall, the actuator means reciprocates when activated; at least one cutting device attached to the target wall of each of the fluid collection chamber and fluid dispenser chamber and extending away from the respective chambers, each such cutting device having a passage for transporting fluid there through; and a power supply operatively connected to the actuator means for activating the actuator, the actuator means reciprocates in an upward and downward motion relative to the interior of the respective chambers when activated, whereby the upward motion contracts the volume of the fluid dispenser chamber to provide a positive pressure in the fluid dispenser chamber relative to the pressure of the target, whereby the positive pressure causes the fluid to be transported from the fluid dispenser chamber into the target, and whereby the upward motion expands the volume of the collection chamber to provide a negative pressure in the fluid collection chamber relative to the pressure of the target whereby the negative pressure causes the fluid to be transported from the target into the fluid collection chamber.
Further, an additional embodiment of the present invention is a fluid transport apparatus for withdrawing fluid from a target, whereby the target has target passages extending therein, the fluid transport apparatus comprising: at least one fluid collection chamber having a target wall and a distal wall opposite of the target wall, whereby the target wall is adapted for being mated against the target while the transport apparatus is in use; an actuator means that is in mechanical communication with the distal wall, the actuator means reciprocates when activated; at least one aperture disposed on the target wall of the fluid collection chamber so as to be aligned with the respective target passage when the target wall is mated against the target, thereby forming a passage between the target passage and the target wall aperture for transporting fluid there through; and a power supply operatively connected to the actuator means for activating the actuator, the actuator means reciprocates in an upward and downward motion relative to the target when activated, whereby the upward motion expands the volume of the collection chamber to provide a negative pressure in the fluid collection chamber relative to the pressure of the target whereby the negative pressure causes the fluid to be transported from the target into the fluid collection chamber.
Finally, another embodiment of the present invention is a method of transporting fluid from a target using a fluid transport apparatus, the method comprising the steps of: inserting at least one cutting device into the target wherein the cutting device comprises a passage for transporting fluid there through to a fluid collection chamber, the fluid collection chamber comprising a target wall that is adapted for being mated against the target while the transport apparatus is in use, the fluid collection chamber having a distal wall that is opposite the target wall; and applying a negative pressure in the fluid collection chamber, wherein the negative pressure causes the fluid to be transported or withdrawn from the target into the passages of the cutting devices and transported or withdrawn into the fluid collection chamber. Wherein the application of negative pressure comprises the following steps: expanding the volume of the fluid collecting chamber via a fluid valve means disposed on the target wall. Wherein the volume expansion of the fluid collection chamber comprises the following steps: activating an actuator means that is in mechanical or electrical communication with the distal wall; the actuator means reciprocates causing the distal wall to reciprocate in an upward and a downward motion relative to the target when activated, whereby the upward motion expands the volume of the fluid collection chamber to provide the negative pressure in the fluid collection chamber relative to the pressure of the target and whereby the negative pressure causes the fluid to be transported from the target into the fluid collection chamber.